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@pklaus
pklaus / ping.py
Created March 5, 2011 09:50
A pure python ping implementation using raw socket.
#!/usr/bin/env python2
"""
Other Repositories of python-ping
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* https://github.com/l4m3rx/python-ping supports Python2 and Python3
* https://bitbucket.org/delroth/python-ping
@Marak
Marak / hack.sh
Created March 31, 2012 22:30 — forked from erikh/hack.sh
OSX For Hackers
#!/usr/bin/env sh
##
# This is script with usefull tips taken from:
# https://github.com/mathiasbynens/dotfiles/blob/master/.osx
#
# install it:
# curl -sL https://raw.github.com/gist/2108403/hack.sh | sh
#
@jboner
jboner / latency.txt
Last active July 3, 2024 09:19
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@brandonb927
brandonb927 / osx-for-hackers.sh
Last active June 13, 2024 02:39
OSX for Hackers: Yosemite/El Capitan Edition. This script tries not to be *too* opinionated and any major changes to your system require a prompt. You've been warned.
#!/bin/sh
###
# SOME COMMANDS WILL NOT WORK ON macOS (Sierra or newer)
# For Sierra or newer, see https://github.com/mathiasbynens/dotfiles/blob/master/.macos
###
# Alot of these configs have been taken from the various places
# on the web, most from here
# https://github.com/mathiasbynens/dotfiles/blob/5b3c8418ed42d93af2e647dc9d122f25cc034871/.osx
@jbenet
jbenet / simple-git-branching-model.md
Last active June 17, 2024 14:53
a simple git branching model

a simple git branching model (written in 2013)

This is a very simple git workflow. It (and variants) is in use by many people. I settled on it after using it very effectively at Athena. GitHub does something similar; Zach Holman mentioned it in this talk.

Update: Woah, thanks for all the attention. Didn't expect this simple rant to get popular.

@XVilka
XVilka / TrueColour.md
Last active June 27, 2024 11:24
True Colour (16 million colours) support in various terminal applications and terminals

THIS GIST WAS MOVED TO TERMSTANDARD/COLORS REPOSITORY.

PLEASE ASK YOUR QUESTIONS OR ADD ANY SUGGESTIONS AS A REPOSITORY ISSUES OR PULL REQUESTS INSTEAD!

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns                     on recent CPU
L2 cache reference ........................... 7 ns                     14x L1 cache
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns                     20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs 4X memory

import time
import random
import struct
import select
import socket
def chk(data):
x = sum(x << 8 if i % 2 else x for i, x in enumerate(data)) & 0xFFFFFFFF
x = (x >> 16) + (x & 0xFFFF)
@staltz
staltz / introrx.md
Last active July 2, 2024 03:45
The introduction to Reactive Programming you've been missing